Wireless transmitting system



H. K. SANDELL.

WIRELESS TRANSMITTING SYSTEM.

- APPLICATION FILED NOV. 28, 1919.

"1,391,855. PatentedSept. 27, 1921,

vireo STATES PATENT OFFICE.

HENRY n. snn'nnnn, or GHIGAGO, rumors, ASSIGIIOE T0 HERBERT S. MILLS, or

GHICAGO,

- rumors.

WIRELESS TRANSMITTING SYSTEM.

Specification of Letters Patent. Patented Sept.- 27, 1921.

Application filed November 28, 1919. Serial No. 340,998.

cation.

The present invention relates to systems for the transmission f wireless signals, and more particularly to transmitting or sending means whereby signals are transmitted by the use of undamped or continuous waves.

In accordance with the present invention an electron tube or space current device is utilized for the production. of oscillating electrical impulses, which are modified by suitable means for the production of the signals which are to be transmitted. In order to produce'these oscillations the'input circuit of the electron tube is so arranged as to be responsive to changes in the currents in the output circuit thereof, and by its responsiveness to such changes, to produce an oscillating current in the output circuit. The signals to be transmitted are then imposed upon this oscillating circuit;

In the accompanying drawing there is shown in diagrammatic form a system embodying the present invention. In the draws I Figure 1 is a diagrammatic representation of the system, and

Fig. 2 illustrates the relative arrangement of the loops of the system of Fig. 1.

In the drawing, the numeral 5 indicates an electron tube or space current device, for example, of the audion type, having a filament 6, a grid 7 and a plate 8, the filament 6 being heated by means of a suitable battery 9. The plate is connected by conductor 10 to the positive pole of the battery 11, and the output circuit is completed by the connection 12 to the negative pole of the battery 11,.the aerial 13 shown as of the spiral or loop type, and the conductor 1i leading to the filament 6. The aerial or loop mentioned loop.

the loop or aerial 19, and conductors 20 and 21 which connect at 22 with the conductor 14 leading in to the filament 6. In order to produce the desired variations in the oscillatlng current in the output circuit, the secondary 23 of a transformer may be c0nnected in the series in the input circuit, the primary 24 being connected in series with the transmitter 25 and the battery 26. v

The loop for the aerial 19 is rotatably mounted upon a suitable standard 27 from which it is insulated, and is placed in proximity to the loop 13 of the output circuit, as indicated in Fig. 2. Its angular position relative thereto may be varied by rotating it to any desired position.

In operation, on closing the output or plate circuit, the reaction produced upon the loop or aerial 19 in the intake circuit results in the production of oscillating currents in the output circuit, the two loops acting as a coupling for the production of this effect. By varying the angular position ofv the loop 19 relative to the loop 13, the conditions for most eificient operation may be readily determined. By use of the transmitter 25 or other signaling device, variations in the cur rent in the input circuit maybe produced, which are reproduced in the output circuit by which they are transmitted as impressed upon the oscillating circuit therein. It is readily apparent that the signals may be directly impressed upon the output circuit instead. of upon the input circuit, but the latter method is preferred byreason of its greater efficiency.

It is furthermore apparent that the mutual reaction of the output and input circuits whereby the oscillating current in the output circuit is produced may likewise be produced by the use of other coupling devices,

'for example, by coils. \It is furthermore to be understood that the specific details of the. system herein described are not intended to be regarded as limitations upon the scope of the invention, except in so far as included in the accompanying claims.

I claim: y

1. In a wireless transmitting system, an electron tube having an input and an output circuit, a loop aerial in series in the input circuit, and a loop aerial in series in the output circuit and in proximity to the first 2. In a wireless transmitting system, an

electron tube having an input and an output circuit, a grounded loop aerial in series in the output circuit, a loop aerial in series in the input circuit, said loops being in proximity to each other and their relative angular positions being variable.

3. In a ireless transmitting system, an electron tube having an input and an output circuit, a grounded loop aerial in series in the output circuit, a loop aerial in series in the input circuit, a transformer, the secondary of which is in series in the input circuit, and means for producing variations in the primary of said transformer.

HENRY K. SANDELL. 

